Soil organic carbon can now be mapped with a simple technique using satellite imaging.

Environmental Research Web reports on a technique developed by Tor-Gunnar Vågen from the World Agroforestry Centre and Leigh Winowiecki from the International Centre for Tropical Agriculture.

Previously, analysing soil organic carbon has involved the time-consuming and sensitive technique of analysing bulk density cores. But now, soil at various depths can be collected using an auger and analysed in the laboratory with the bulk density and/or soil mass mapped for any given depth.

The technique, which the scientists say allows for repeatable and robust measurements in different soil types, has enabled soil organic carbon stocks to be mapped using Landsat ETM+ reflectance across four study sites in East Africa; something that would not have been possible with conventional methods.

In conducting their research, the scientists found that soil erosion had a significant affect on soil organic carbon stocks. They also found that “inherent soil properties such as sand content are often more important than climate effects alone in determining soil organic carbon dynamics,” says the article.

The findings are important in guiding better land management practices. For example, in dryland areas, managing woody cover alone will not be enough to reduce erosion. Strategies will need to focus on improving the condition of the herbaceous cover such as improved grazing and better livestock management.

Read the full story: New technique simplifies soil organic carbon measurement